The product of conductivity and resistivity of a conductor
[amp_mcq option1=”depends on pressure applied” option2=”depends on current flowing through conductor” option3=”is the same for all conductors” option4=”varies from conductor to conductor” correct=”option3″]
This question was previously asked in
UPSC NDA-1 – 2015
Resistivity ($\rho$) and conductivity ($\sigma$) are inverse properties of a material concerning its ability to conduct electricity.
By definition, conductivity is the reciprocal of resistivity ($\sigma = 1/\rho$). Therefore, the product of conductivity and resistivity is always equal to 1 ($\sigma \times \rho = (1/\rho) \times \rho = 1$). This relationship holds true for all materials, regardless of whether they are conductors, insulators, or semiconductors, and it is independent of the physical conditions like pressure or the current flowing through the conductor (assuming the material obeys Ohm’s Law).